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Load_IFF() PCHG chunk to support "Palette Change" ILBMs

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This commit is contained in:
Thomas Bernard 2018-02-04 02:09:26 +01:00
parent d59c7b6d26
commit 039f9af663
1 changed files with 194 additions and 2 deletions
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196
src/fileformats.c
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@ -335,6 +335,12 @@ void Test_ACBM(T_IO_Context * context)
// -- Lire un fichier au format IFF -----------------------------------------
typedef struct T_IFF_PCHG_Palette {
struct T_IFF_PCHG_Palette * Next;
short StartLine;
T_Components Palette[1];
} T_IFF_PCHG_Palette;
// Inspired by Allegro: storing a 4-character identifier as a 32bit litteral
#define ID4(a,b,c,d) ((((a)&255)<<24) | (((b)&255)<<16) | (((c)&255)<<8) | (((d)&255)))
@ -431,6 +437,25 @@ static void Draw_IFF_line(T_IO_Context *context, const byte * buffer, short y_po
}
}
static void Draw_IFF_line_PCHG(T_IO_Context *context, const byte * buffer, short y_pos, short real_line_size, byte bitplanes, const T_IFF_PCHG_Palette * PCHG_palettes)
{
const T_IFF_PCHG_Palette * palette;
short x_pos;
palette = PCHG_palettes; // find the palette to use for the line
if (palette == NULL)
return;
while (palette->Next != NULL && palette->Next->StartLine <= y_pos)
palette = palette->Next;
//printf("%d %p %d\n", y_pos, palette, palette->StartLine);
for (x_pos=0; x_pos<context->Width; x_pos++)
{
dword c = Get_IFF_color(buffer, x_pos,real_line_size, bitplanes);
Set_pixel_24b(context, x_pos,y_pos, palette->Palette[c].R, palette->Palette[c].G, palette->Palette[c].B);
}
}
static void Draw_IFF_line_HAM(T_IO_Context *context, const byte * buffer, short y_pos, short real_line_size, byte bitplanes, const T_Components * SHAM_palettes, int SHAM_palette_count)
{
short x_pos;
@ -591,6 +616,7 @@ void Load_IFF(T_IO_Context * context)
unsigned SHAM_palette_count = 0;
byte truecolor = 0;
byte Image_HAM = 0;
T_IFF_PCHG_Palette * PCHG_palettes = NULL;
Get_full_filename(filename, context->File_name, context->File_directory);
@ -656,6 +682,7 @@ void Load_IFF(T_IO_Context * context)
&& header.Width && header.Height)
{
byte real_bit_planes = header.BitPlanes;
nb_colors = 1 << real_bit_planes;
if (header.Mask==1)
header.BitPlanes++;
Back_color=header.Transp_col;
@ -802,6 +829,161 @@ void Load_IFF(T_IO_Context * context)
fseek(IFF_file, (section_size+1)&~1, SEEK_CUR);
}
}
else if (memcmp(section, "PCHG", 4) == 0)
{
dword * lineBitMask;
int i;
T_IFF_PCHG_Palette * prev_pal = NULL;
T_IFF_PCHG_Palette * curr_pal = NULL;
void * PCHGData = NULL;
// http://wiki.amigaos.net/wiki/ILBM_IFF_Interleaved_Bitmap#ILBM.PCHG
// http://vigna.di.unimi.it/software.php
// Header
word Compression; // 0 = None, 1 = Huffman
word Flags; // 0x1 = SmallLineChanges, 0x2 = BigLineChanges, 0x4 = use alpha
short StartLine; // possibly negative
word LineCount;
word ChangedLines;
word MinReg;
word MaxReg;
word MaxChanges;
dword TotalChanges;
if (!(Read_word_be(IFF_file, &Compression)
&& Read_word_be(IFF_file, &Flags)
&& Read_word_be(IFF_file, (word *)&StartLine)
&& Read_word_be(IFF_file, &LineCount)
&& Read_word_be(IFF_file, &ChangedLines)
&& Read_word_be(IFF_file, &MinReg)
&& Read_word_be(IFF_file, &MaxReg)
&& Read_word_be(IFF_file, &MaxChanges)
&& Read_dword_be(IFF_file, &TotalChanges)))
File_error = 1;
section_size -= 20;
if (Compression)
{
short * TreeCode;
const short * TreeP; //a3
int remaining_bits = 0; //d1
dword src_dword = 0; //d2
byte * dst_data; //a1
dword CompInfoSize;
dword OriginalDataSize; //d0
Read_dword_be(IFF_file, &CompInfoSize);
Read_dword_be(IFF_file, &OriginalDataSize);
section_size -= 8;
// read HuffMan tree
TreeCode = malloc(CompInfoSize);
for (i = 0; i < (int)(CompInfoSize / 2); i++)
Read_word_be(IFF_file, (word *)(TreeCode + i));
section_size -= CompInfoSize;
PCHGData = malloc(OriginalDataSize);
dst_data = PCHGData;
// HuffMan depacking
TreeP = TreeCode+(CompInfoSize/2-1); // pointer to the last element
while (OriginalDataSize > 0)
{
if (--remaining_bits < 0)
{
Read_dword_be(IFF_file, &src_dword);
section_size -= 4;
remaining_bits = 31;
}
if (src_dword & (1 << remaining_bits))
{
if (*TreeP < 0)
{
// OffsetPointer
TreeP += (*TreeP / 2);
continue; // pick another bit
}
}
else
{
// Case0
--TreeP;
if ((*TreeP < 0) || !(*TreeP & 0x100))
continue; // pick another bit
}
// StoreValue
*dst_data = (byte)(*TreeP & 0xff);
dst_data++;
TreeP = TreeCode+(CompInfoSize/2-1); // pointer to the last element
OriginalDataSize--;
}
free(TreeCode);
}
else
{
PCHGData = malloc(section_size);
Read_bytes(IFF_file, PCHGData, section_size);
section_size = 0;
}
if (PCHGData != NULL)
{
const byte * data;
// initialize first palette from CMAP
prev_pal = malloc(sizeof(T_IFF_PCHG_Palette) + nb_colors*sizeof(T_Components));
prev_pal->Next = NULL;
prev_pal->StartLine = 0;
memcpy(prev_pal->Palette, context->Palette, nb_colors*sizeof(T_Components));
PCHG_palettes = prev_pal;
lineBitMask = PCHGData;
#if SDL_BYTEORDER != SDL_BIG_ENDIAN
for (i = 0 ; i < ((LineCount + 31) >> 5); i++)
lineBitMask[i] = SDL_Swap32(lineBitMask[i]);
#endif
data = PCHGData + ((LineCount + 31) >> 5) * 4;
for (y_pos = 0 ; y_pos < LineCount; y_pos++)
{
if (lineBitMask[y_pos >> 5] & (1 << (31-(y_pos & 31))))
{
byte ChangeCount16, ChangeCount32;
word PaletteChange;
if ((y_pos + StartLine) < 0)
curr_pal = PCHG_palettes;
else
{
curr_pal = malloc(sizeof(T_IFF_PCHG_Palette) + nb_colors*sizeof(T_Components));
curr_pal->Next = NULL;
curr_pal->StartLine = StartLine + y_pos;
memcpy(curr_pal->Palette, prev_pal->Palette, nb_colors*sizeof(T_Components));
prev_pal->Next = curr_pal;
}
ChangeCount16 = *data++;
ChangeCount32 = *data++;
for (i = 0; i < ChangeCount16; i++)
{
PaletteChange = data[0] << 8 | data[1]; // Big endian
data += 2;
curr_pal->Palette[(PaletteChange >> 12)].R = ((PaletteChange & 0x0f00) >> 8) * 0x11;
curr_pal->Palette[(PaletteChange >> 12)].G = ((PaletteChange & 0x00f0) >> 4) * 0x11;
curr_pal->Palette[(PaletteChange >> 12)].B = ((PaletteChange & 0x000f) >> 0) * 0x11;
}
for (i = 0; i < ChangeCount32; i++)
{
PaletteChange = data[0] << 8 | data[1]; // Big endian
data += 2;
curr_pal->Palette[16+(PaletteChange >> 12)].R = ((PaletteChange & 0x0f00) >> 8) * 0x11;
curr_pal->Palette[16+(PaletteChange >> 12)].G = ((PaletteChange & 0x00f0) >> 4) * 0x11;
curr_pal->Palette[16+(PaletteChange >> 12)].B = ((PaletteChange & 0x000f) >> 0) * 0x11;
}
prev_pal = curr_pal;
}
}
free(PCHGData);
}
fseek(IFF_file, (section_size+1)&~1, SEEK_CUR);
if (PCHG_palettes != NULL)
truecolor = 1;
}
else if (memcmp(section, "TINY", 4) == 0)
{
word tiny_width, tiny_height;
@ -909,7 +1091,9 @@ printf("%d x %d = %d %d\n", tiny_width, tiny_height, tiny_width*tiny_height, s
{
if (Read_bytes(IFF_file,buffer,line_size))
{
if (Image_HAM <= 1)
if (PCHG_palettes)
Draw_IFF_line_PCHG(context, buffer, y_pos,real_line_size, header.BitPlanes, PCHG_palettes);
else if (Image_HAM <= 1)
Draw_IFF_line(context, buffer, y_pos,real_line_size, header.BitPlanes);
else
Draw_IFF_line_HAM(context, buffer, y_pos,real_line_size, header.BitPlanes, SHAM_palettes, SHAM_palette_count);
@ -967,7 +1151,9 @@ printf("%d x %d = %d %d\n", tiny_width, tiny_height, tiny_width*tiny_height, s
}
if (!File_error)
{
if (Image_HAM <= 1)
if (PCHG_palettes)
Draw_IFF_line_PCHG(context, buffer, y_pos,real_line_size, header.BitPlanes, PCHG_palettes);
else if (Image_HAM <= 1)
Draw_IFF_line(context, buffer, y_pos,real_line_size,header.BitPlanes);
else
Draw_IFF_line_HAM(context, buffer, y_pos,real_line_size, header.BitPlanes, SHAM_palettes, SHAM_palette_count);
@ -1127,6 +1313,12 @@ printf("%d x %d = %d %d\n", tiny_width, tiny_height, tiny_width*tiny_height, s
File_error=1;
if (SHAM_palettes)
free(SHAM_palettes);
while (PCHG_palettes != NULL)
{
T_IFF_PCHG_Palette * next = PCHG_palettes->Next;
free(PCHG_palettes);
PCHG_palettes = next;
}
}